Various cutting tools are used in metal/wood cutting and the like. Particularly, in petroleum and gas drilling fields, the ground needs to be cut and excavated, and thus digging and excavating equipment in which abrasion resistance can be ensured as much as possible is used.
A cutting tool 1 is provided at an end of the equipment as illustrated in FIG. 1. In general, the abrasion resistance may be sufficiently ensured at the end of the cutting tool 1 by using a diamond compact 2 in spite of friction with the ground.
In FIG. 2, an appearance of a general diamond compact 2 is illustrated. As illustrated in FIG. 2, a polycrystalline diamond compact includes a cemented substrate 4 and a polycrystalline diamond sintered body 3 which is sintered by using diamond powder on the cemented substrate 4. The cemented substrate 4 serves to support the polycrystalline diamond compact 2 to be attached to various tools and the like while the polycrystalline diamond sintered body 3 is attached.
Meanwhile, outer edges of the polycrystalline diamond compact are first heated due to a characteristic of a sintering process under high temperature and high pressure. For this reason, a difference in temperature between a center and the outer edges of the polycrystalline diamond compact is generated during sintering to have a difference in sinterability.
During sintering, according to a characteristic of the final desired polycrystalline diamond compact, an optimal sintering temperature is set. In this case, when the sintering temperature is too low or too high, properties of the polycrystalline diamond compact such as impact resistance or abrasion resistance deviates from a range of the desired properties and thus defects of the product are generated.